1. Technical Field
The present disclosure relates to an ultrasonic bonding jig, an ultrasonic bonding method, and a bonding structure.
2. Description of the Related Art
In ultrasonic bonding, a metal plate and a metallic base material are stacked and placed on a support table. In this state, while the metal plate is pressed by an ultrasonic bonding jig, ultrasonic vibration is performed on the ultrasonic bonding jig at a predetermined frequency in a horizontal direction. Thus, pressing force and the ultrasonic vibration from the ultrasonic bonding jig act on opposed surfaces of the metal plate and the base material. Consequently, an oxide and other dirt on surfaces of the metals are removed. Furthermore, friction heating generated by the pressing force and the ultrasonic vibration generates bonding between metal atoms.
A chip (an ultrasonic bonding jig) disclosed in WO 2013/105361 A (the ninth page, the second drawing) includes a plurality of protrusions arranged in a grid pattern on a processed surface abutting on an electrode laminated body (a metal plate). Chamfers are provided on a contour line of the protrusions disposed on an outermost periphery among the plurality of protrusions such that the protrusions have an arc having a radius R meeting R≥A/6 when an external dimension in the one direction is defined as A. This restrains a break of the electrode laminated body caused by ultrasonic bonding.